1. Field of Invention
This invention relates to electro-optical imaging systems. Specifically, the present invention relates to systems and methods for capturing and analyzing digital video data from a sensor array.
2. Description of the Related Art
Electro-optical energy sensors are employed in various applications including commercial digital cameras, industrial thermal imaging cameras, infrared night-vision systems, and missile guidance systems. Such applications often demand high-quality sensors with predetermined performance characteristics. Accordingly, special sensor-testing equipment is required to verify sensor characteristics before use in a given application. Newly manufactured sensor arrays are often discarded or employed in less demanding applications if their characteristics do not match certain criteria.
Sensor arrays are typically two-dimensional arrays of electromagnetic energy detectors. Examples include Charge-coupled Devices (CCD's), commonly employed in digital cameras and Focal Plane Arrays (FPA's), commonly employed in infrared and microwave applications.
Sensor array applications often require accurate and uniform arrays of sensors.
To verify sensor array quality, the sensor arrays are tested for bad pixels, nonuniformities, and other defects and performance characteristics via special testing equipment.
Sensor arrays with different size, type, and performance characteristics are often required for different applications. Equipment employed to test sensor arrays is typically redesigned for each application in accordance with the differing application specifications. Redesign of the testing equipment may require costly new hardware, such as video capture subsystems and other digital image acquisition and analysis circuits suited to output application-specific sensor array characteristics.
Furthermore, conventional image acquisition and analysis systems employed to characterize sensor arrays typically lack flexibility and adaptability (and lack extensibility interfaces); as they are hard-wired for particular applications. Furthermore, these application-specific systems often have significant data acquisition limitations, such as the amount of image data that can be stored and analyzed, which may undesirably limit the accuracy of the testing equipment.
Conventional systems include the PC-DAS and the ASRAAM VAP systems. The PC-DAS is a PC-based system for capturing and analyzing infrared (IR) FPA video. The system has very limited capacity and accuracy and can only capture 64 frames output from a 128×128 FPA. The system lacks mechanisms for saving all original data. Furthermore, the system is application-specific, only working with 128×128 or 256×256 FPA's.
The ASRAAM VAP is PC-based system for capturing and analyzing IR FPA video. Unfortunately, this system is also application-specific, supporting only 128×128 FPA's. Video analysis algorithms are hosted on the video capture subsystem, making the system non-portable. Stand-alone operation of the system requires software modification. The system also has limited storage capacity and can only capture 480 frames output from a 128×128 FPA. Both the ASRAAM VAP system and the PC-DAS are controlled by 16-bit DOS applications with 640 kilobyte memory limitations and both lack extensibility interfaces.
Thus, certain sensor array sizes and characteristics, such as numbers of dead pixels and nonuniformity characteristics, are required for some sensor-testing applications and not required for others. Accordingly, any special requirements are typically met by custom designing and building image acquisition and analysis systems for analyzing sensor array characteristics. System redesign is particularly costly for companies that develop sensor arrays for multiple applications.
Hence, a need exists in the art for a versatile, flexible system for acquiring an image or video from a sensor array and analyzing the acquired image. There is a further need for a video acquisition and analysis system that may be inexpensively optimized for a particular application without requiring costly redesign of the same.